Drilling hook



Oct. 12, 1943.

G. F. NICOLSON ETAL' DRILLING HOOK Filed Jan. 9, 1942 3 Sheets-Sheet 12. 6.42m E McaLso/v Ava/A20 A. #5,? TEL,

INVENTORS BY nfizww/ Afro/away.

Oct. 12, 1943. G. F. NICOLSON ET AL ,3 4

DRILLING HOOK Filed Jan. 9, '1942 a Sheets-Sheet 2 GARTH f. /V/COL so/v,RICHARD/I. HER TEL,

INVENTORS ATTORNE y.

Oct-"1'2, 1943. v G. F. NlcoLsoN ET AL 3 9 DRILLING HOOK Filed Jan. 9,1942 5 Sheets-Sh'eet 5 GARTH E NICOLIO/V,

film/4R0 A. file/era,

INVENTORS Arron/Ev.

Patented Oct. 12, 1943 DRILLING HOOK Garth F. Nicolson, Huntington Park.and Rich: ard K. Hertel, Los Angeles, Calif.,' assignors to ByronJackson 00., Huntington Park, Ca1if., a

corporation of Delaware Application January 9, 1942, Serial'No. 426,196

7 Claims.

' .This invention relates generally to drilling A general object of theinvention is to provide a hook of exceptionally rugged and durableconstruction and embodying improved features designed to betterwithstand the severe service to which rotary and casing hooks aresubjected.

Another object is to provide an improved construction for releasablylocking the hook member of a spring hook against rotation with respectto 'thesupporting housing. Other objects and advantages will be apparentfrom the following detailed description of one embodiment of theinvention, reference being had to the accompanying drawings wherein:

Fig. l is an elevation of a complete hook assembly embodying theinvention;

Fig. 2 is a View, partly in elevation and partly in section, taken atright angles to Fig. 1;

Fig. 3 is an enlarged fragmentary longitudinal sectional viewof thecentral portion of the hook, showing the swivel lock sleeve rotatedthrough 180 from the position shown in Fig. 2;

Fig. 4- is a transverse section taken on line IV-IV of Fig. 3;

Fig. 5 is a transverse section taken on line VV of Fig. 3;

Fig. 6 is an elevation of the portion of the hook shown in Fig. 3, asviewed from the right-hand side of the latter figure, with parts brokenaway on line VI-VI of Fig. 3;

Fig. '7 is a transverse section taken on line VII-VII of Fig. 6;

Figs. 8 and 9 are views showing the swivel locking member in twodifferent positions from that illustrated in Fig. 3;

Fig. 10 is a fragmentary elevational view of the swivel lock housing, asviewed from the right of Fig. 6;

Figs. 11 and 12 are enlarged fragmentary sectional views of the upperportion of the hook, il-

lustrating the swivel bearing in two positions; and 3 Fig. 13 is alongitudinal section taken on line XIII-XIII of Fig. 1. I

Referring to the drawings, and particularly to Figs. 1 and 2,theinvention has been shown as incorporated in a hook comprisinggenerally a hook body I pivotally connected to the lower extremity of ashank 2 by a'pivot pin 3, the shank 2 being yieldably supported in ahousing 4. A yoke or bail 5 is connected t the upper end of thehousingfor connecting the hook to the usual traveling block. In accordance withusual prac tice, the shank 2 isyieldably supported. in the housing by acoil compression spring 6 interposed between a nut 1 threaded'to theupper end of the shank and an inwardlyprojecting shoulder 8 at the lowerend of the'housing. Downward moveinent-of the shank and book, as thespring is compressed under load, is limited by a stop shoulder 9 formedin the housing 4.

It-will be observed that the nut I is threadedly connected to the shank2 by a relatively coarse left-handthread I 2, preferably of the modifiedAcme type, although it will be appreciated that any other type of threadmay be used. The hook is most frequentlyrotated in clockwise direction,as viewed from above, as when making up the joints between sections ofdrill pipe or casing, and

hence the provision of a left-handthread tends to cause the nut totighten instead of loosen during rotation. The thread is of the straighttype, rather than tapered, and the nut is made up against a shoulder 13on the shank 2. The nut l .is securely locked inengagement with theshoulder I3 by alocknut-M which is threadedly connected to a reducedextension I5 on the shank, by

a relatively fine left-hand thread l6 of less pitch than the thread l2.The lock nut is made up tightly against a flat shoulder on the uppersurface of the nut l, and, due to the difference in pitch of the twothreads, a powerful wedging ef fect is obtained. However, as a furthersafeguard against inadvertent loosening of the lock nut. a-set screw I1is preferably threaded in the lock nut and engages the shank extensionI5 above the threads I6.

A sturdy and compact swivel locking arrangement has been provided, for'releasably locking a splined connection between the shank and a locksleeve l9. As seen most clearly in Fig. 5, the lower portion of thesleeve l9, below the stop shoulder 8 on the housing 4, is provided with'a square opening 20 closely fitting the square portion of the shank.The sleeve extends upwardly around thedower cylindrical portion; of thehousing 4, and-is rotatably supported thereon by a split clamp ring 24(Figs. 3, 6 and 7).

' As shown-in Fig; 3, the outer wall of the housannular rib 29 housedwithin the recess 28 and providing a rotatable interlocking connection.

between the lock sleeve and the clamp ring. The

lock sleeve is thus mounted on the housing. 4 for rotation with theshank 2 and hook body t, but is constrained against axial movement withrespect to the housing.

In order to releasably lock the shank 2- against rotation with respectto the housing 4, a releasable locking connection is provided betweenthe housing and the lock sleeve [9. As shown. most clearly in. Fig. 4, aplurality of circumferehtially spaced slots 32 are formed in the lowerportion of the housing 4, and a locking member 33 ispiy-v otally,mounted on and enclosed within; a laterally projecting housing 34;formed integral with the lock sleeve 19, the member 33 being movableradially into or out ofengagement with a selected one ofthe slots 32;The locking member isrsuitably keyed to a rock shaft 35 journaled in thehousing 34:, and for this. purpose the centraliportion of the rock shaftis provided; with a pair of oppositely extending ribsor keys 36 and 3;!which engage similarly shapedkeyways 38 and 38ginthe hub of the lockingmember. To enable therock shaft 35 to be manually oscillated about itsaxis, and thus movethe-locking member into or out of engagement with oneof the slots 32, one end of the rock shaft projects through the wall, ofthe housing 34' and: is provided with an enlargedahead on. which areformed a pairof hook-shaped projections4 t and 42., as shown in Fig. 10.When the locking'member-33 is in. the-locking position shown in Fig. 3,the head 4!) assumes theiposie tion indicated in solidlines in- Fig. 10.Ifr it is desired to move the lockingmember to its-released position(Fig. 8), a downwardpull: is exerted on the projection 4 lby means ofthe usual shepherd's hook provided for that purpose; to rock the shaftin counter-clockwise direction; as viewed in Fig. 10; the head-40 thenassuming the dottedline position indicated in the latter-figure.Similarly, a downward pull on the projection 42 causes the lockingmember'to move from released to locked position.

A spring toggle mechanism is associated with therlocking member 33'for'yieldably maintaining thelockingjme'chanism in either looking orreleased position. As shown most clearly in Figs. 3,

'6, 8 and 9, a double-faced cam 45 isformed integral with and projectsoutwardly from the hub of the locking member, and is provided withoppositely directed cam faces 46 and 41'. One

cam face or the other. is adapted to be selectively engaged by a roller48 mounted on the freeend of a rocker arm 49 journaled on a pin on bolt50 mounted in the housing 34. and extending parallel to the rock shaft35. The rocker, arm. is yieldingly urged in a counter-clockwisedirection, a s viewecl in Figs. 3, 8, and 9, by a torsion. spring 5]having one end thereof engaging an abutment 52 onthe housing;34 and theother end engaging an abutment 53 on the rocker arm.

Thus. when the locking member is in, thelocking position shown in Fig.3, the roller 48 engages the cam face 41 and urges it incounter-clockwise direction, thus yieldingly maintaining the lockingmember in this position. As the rock shaft 35 is rotated to move thelocking member to its released position, the cam face 41 forces therocker arm downwardly against the action of the spring 51, until theroller passes the apex of the cam and engages theother cam face 46.Thereupon the rocker arm urges the locking member in clockwisedirection, moving it into the released position indicated in Fig. 8.

t will be observed, with particular reference t,o;Figs. 3; and 9, thatthe locking member 33 is pnoizidedi with. two angularly disposed faces55 and 58- on the side thereof facing the housing 4.

Theupper-faoe 55 is so disposed that, when the locking member engagesone of the slots Hi, the face 55 extends parallel to the axis of theshank 2 andflush with the inner wall of the housing, a pair.- of,laterally extending wings 5,1 and 58. (Fig. 6) being providedlonthelocking member to limit its inward movement, The lower face 55 isangularly disposedwith respect to the upper face 5,5, so that if thelocking member should be rocked inwardly but. should not align with oneof' the slots l9, the face 56 will extend parallel to the outer wall ofthe housing 41 whenit engages the latter, as indicated in,Fig. 9. Itwill be observed that ln.tl1i. .PO l n of the lock n e ber,, h roller4.8..engases the. nner am, a IandIuIs s the locking member toward,locking position. It will thereforebe evident that if the hook body land shank,2-.ar.e then rotated, slightly, to align the nextadjacentslot,3 2 with the locking member, the latter will. automatically snapinto. the slotun'der the action of the spring 5|, This arrangementdispenseswith the necessity of, maintaining a. downward manual. pull on,thc projection 42 while, the, hook. is. being, rotated, to align a slot.32, with, the locking, memben,

Itwiil be understood. by those familiar. with rotary and. casing hooksthat. the spring. 5 is only of sufficient strength to, support a singlestandvof, drill pipe, and that when the entire drill string is suspendedfrom the hook the spring compresses and allowsthe hook body and shank todescend until the stop shoulder isengaged, thus transferring, the load.directly, from the shanknut T, to, the stop shoulder. It hasbeencustomary. to interpose an anti-friction bearing between the shank nutand, the stop shoulder to provide free swivelling of, the hook body nderfull load when this is desired, In, prior constructions the same bearinghas alsobe n so. arranged as to; beinterposed between, the upperextremity of the spring and thejlower faceof the shank nut, in order toprovide free swiveling of the shank and nutwith, respect tothe spring.

s n l arin crp sed between. the. shan nut and b h he Shrine and. the sp. shoulder s, how r, b ec ionabl for. h f lg nsfieason:

Durin the drill ng. operat n. hexwcisht of the drill' string is.transiferred' from the hook shank, to. he m sing. throu th hank. nut andthe bearing. The hook is locked against rotation during drilling, andhence for long periods of time each of the bearing balls or'rollersoccupies a fixed position with respect to the bearing races, and thevibration and'the gyratory motion transmitted to the'hook from the drillstring during drilling often causesthe bearing members to wear groovesor indentations in the bearing races. It is obvious that the presence ofa seriesof indentations in the bearing races interferes with the freedomof rolling action when it is desired to rotate the hook, and this isparticularly noticeable when the hookis rotated manually to orienttheelevator.

In order to overcome the aforementioned dif-" fi'culty, we have provideda bearing construction incorporating a main bearing 60 (Figs. 11 and 12)interposed between the shank "nut '1 and the stop shoulder 9, and anauxiliary bearing 6| interposed between the shank nut and the upper endof the spring 6. Since the spring 6 is always maintained under aninitial pre-compression, the auxiliary bearing is retained thereby inengagement with the nut l and moves vertically with the nut duringcompression and expansion of the spring. It is also deemed preferable tomount the main bearing in such 'amanher that it also movesverticallywith the "nut. To accomplish this, a dual bearing retainer 62 isprovided, and it will be observed that this retainer not only maintainsthe races and balls of each bearing is assembled relation, but alsoserves to support the main bearingBO from the auxiliary bearing 6|. j

The retainer comprises a one-piece structure which may be pressed toshape from sheet stock, with the upper and lower extremities initiallystraight to permit the auxiliary bearing 6| to be inserted from theupper end and the main bearinglii] to be applied from the lower end.After the bearings are assembled on the retainer, the upper edge isrolled inwardly to form a lip 63, and the lower edge is rolled outwardlyto form a lip 64, to securely retain the hearings in place. Attention isdirected to the fact that the retainer issupported by the upper race 65of the bearing 6|, and that a clearance is provided between thelowerrace 66 of that bearing and an upwardly facing inclined shoulder 61 onthe retainer. In a similar manner, the spacing of the lower outwardlybent lip 64 and the downwardly facing shoulder 68 on theretainer is suchas to provide clearance between one of these shoulders and therespectivera'ce 69 or 10 of the bearing 66. These clearances areexaggerated in Figs. 11 and 12 of the drawings, for illustrativepurposes, and in actual practice may be only a few thousandths of aninch.

When the spring 6 is expanded and the main bearing 68 is out of contactwith the stop shoulder, as indicated in Fig. 11, the'bearing is supported solely by the lower lip 64 of the retainer. During rotation ofthe hook body, shank and shank nut under these circumstances, the mainbearing 60 obviously will rotate as a unit with the retainer 62, the nut1, and the upper race 65 of the auxiliary bearing 6|, relative rotationtaking place between the races 65 and 66 of the auxiliary bearing. Thelatter bearing is never loaded in excess of the compression strength ofthe spring 6, and hence it is not subject tothe grooving action whichoccurs in the main bearing during drilling. It will, therefore, remainin good operating condition for a long period of time, provided it isproperly lubricated.

In Figs. 11 and 12, a lubricant fitting 72 is provided in the nut 1, towhich access is had upon removal of a suitable closure plug (not shown)in the housing 4. A series of openings 13 are provided in the retainer62 in the horizontal plane of the fitting 12, for admitting lubricant tothe bearing 6| Lubricant from this fitting. will also work downwardlyinto the main bearing 60, and, as shown in Fig. 1, the main hearing mayalso be separately lubricated through a fitting 14 in the housing. Inaddition to or in lieu of the fitting 12, a lubricant fitting 15 (Fig.2) may be provided in the nut I, to which access is obtained by removalof the cover plate 16 which closes the upper end of the housing 4.

7 Referring to Fig. 12, wherein the parts are shown in the position theyassume when the hook is heavily loaded, it will be observed that themain bearing is now supported on the stop shoulder 9, and that clearanceis provided between the lower lip 64 of the retainer and the lower race69 of the hearing. The upper race 18 engages the shoulder 68 on theretainer, but this is not objectionable inasmuch as these members rotateas a unit with the nut l and the upper race 65 of the auxiliary bearing.The main bearing provides free swivelling between the Shank nut and thestop shoulder 9, while the auxiliary bearing" enables the nut to irotate freely with respect to the spring 6.

Referring now to Figs. 1 and 13, it will b observed that the hook body Iincludes a bill providing a recess 8| for receiving a load-sustainingmember such as a swivel bail, indicated in dotted lines at 82. closed bya locking arm 83 pivoted to the bill at 84, and suitable latchingmechanism, indicated generally at 85, is provided for releasablylatching the arm in closed position. It is preferable that thelocking'arm be automatically closed as the swivel bail or otherload-carrying member is inserted into the recess 8!, and for thispurpose a closing finger 86 is formed integral with the locking arm andprojects inwardly therefrom so as to be engaged by the bail 82 as thelatter enters the recess8 l. As shown most clearly in Fig. 13, the

closing finger is of inverted U-shape in crosssection, and extendsdownwardly along each side of the bill 88 of the hook a sufiicientdistance to.

embrace the bill when the locking arm is in open position, thus avoidingthe possibility of a member of the drilling crew having his fingerscaught between the closing finger and the upper surface of the bill.

The upper surface 81 of the closing finger is {convex in the plane ofFig. 13, and preferably conforms to the curvature of the under side of astandard swivel bail of the same capacity as the hook. The lower surfaceof the closing finger and the upper surface 88 of the bill 80 are also Iconvex in the plane of Fig. 13, and are preferably concentric with theupper surface 81. In the plane of Fig. 1, the surface 81 is concave,preferably conforming to the cross-sectional contour of the swivel bail82, and the lower surface of the closing finger and the upper surface 88of the bill are also preferably concave, and concentric with the surface81. In this manner, the maximum bearing area isprovided between theswivel bail and the closing finger, and between the latter and the bill80.

From the foregoing description of a preferred embodiment of theinvention, it will be apparent that a drilling hook has been providedwhich is of very rugged and durable construction, and in which thefeatures which, in the past, have The recess is adapted to be proved. tobe most troublesome, have: been' so designed: as .to. eliminatethe-mostfrequent sources of trouble.

It is to: be understood, course, that. the specifie details ofconstruction: shown and described are subject to modification: in.various respects, and that the; invention is: not limitedptol suchdetails: but. is: of. the fullscope of the: appended- We. claim:

1.. In a hook structure; the: combination of a housing member having, acentral bore a shank member mounted in the-bore-f or longitudinalandrotary movement relative thereto, a hook. member supported by one ofsaid-,members, resilient means housing the shank member in the: bore ofthe; housing, member, and means for relea-sably locking, the shank.member against rotation'relativeto the housing member, said meanscomprisF ing a sleeve member rota-tably supported by the housing memberand having a slidable and nonrotatable connection with the shank member,and a locking. member mounted on the sleeve member and movable into andout of locking engagement with the housing member.

2'. In a hook structure, the-combination of a housing member having acentral bore and; a'pair of supporting shoulders longitudinally spacedalong the axis of the bore, a shank member mounted in the bore forlongitudinal and rotary movement relative theretoand having a head atone end thereof, resilientmeans interposed between one of said shouldersand said'heacl, bearing means between the other shoulder and. said head,a, sleeve member rotatably supported by the housing member and having aslidable and nonrotatable connection with a portion of the shank memberremote from said head, and means for ,releasably locking, the sleevemember against rotation relative to the housing member.

3. In a hook structure, the combination: of a housing, member having abore, a shank mounted inthe bore for longitudinal and. rotary movementrelative to the housing memben. a. sleeve member' rotatably supported.by the housing member and having a slidable andnon-rotatabl'e connedtion. with an integral portion of the shank, a-locki-ng member mountedon one of said members and movable into andoutot locking engagement withthe other member, and 7 means yieldably maintaining said locking memberin eitherl'ocked or released position.

4-. In. a hook. structure, the; combination of a housing member having,a' central bore, ashank. mounted in the bore for longitudinal: androtarvmovement. relative to the housing: member, said shank having an integralportion. 05 non-circular cross-section, a sleevemember rotatably,support ed bythe housing. member and having a. non.- circular openingtherein. slidably' andnon-rotate ably receiving the. non-circularportion of the. shank, and, means for releasably locking the sleevemember against. rotation relative. to the housing member.

5. In a hook structure. the combination of a. housing member, a shankmember supported thereby: for longitudinal: and. rotary movementrelative thereto, a. sleeve member rotatabl y supported by the housingmember andhaving a slidable and non-rotatable connection with the shankvmember, a locking member carried by the sleeve member and movable intoand out of look.- ing engagement with the housing. member, and springtoggle means: yieldablvmaintaining the looking member in eitherlocked orreleasedposition.

6. In a hookstructure,- the combination of a housing member, a shankmember supported thereby for longitudinal and rotary movement relativethereto, a sleeve. member surrounding a portion of the housing, memberand having a slidable and I'iOIl lOllflilflblB connection. with theshank member, said housing.v member having. an externalshoulder, anelement. supported on. the shoulder and supporting the sleeve member.for rotation relative to the housing. member,, and means for releasablyloclsing. the sleeve member against rotation relative to the housing.member.

7 In ahook structure, a housing. member having a central bore, a pair otinternal shoulders and an external shoulder on said, member, a shankinsaidbore. and. having, a. pair of abut.- ments,resilient.meansinterposed between oneof said internal shoulders, and oneof said abutments, bearing means interposed between the other, internal.shoulder and. the other abutment, an; element supported. on the.external shoulder, a sleeve member supported by said; element for rotarymovement relative'to thehousing member andhaving; a sl-idableand,non-rotatable connection with said shank, and means. for releasablylocking the sleevemember against rotation rel'ative. to the housingmember.

. GARTH; F. NICOLSON. RICHARD K. HERTEL.

